Research On Accessibility,Network Characteristics Of High-speed Railway And Their Influence On Producer Services In Urban Agglomerations

The high-speed railway network structure has been basically formed in China.High-speed railway is not only an important means of transportation,but also to a certain extent shoulders the important task of driving economic development.Producer service industry is regarded as a powerful engine for industrial transformation and upgrading due to its characteristics of fast growth,knowledge-intensive,cross-border expansion and intermediate services,and plays a leading role in the formation of urban network.The development of producer services in city will directly affect its strategic position in urban network and industrial value chain.High-speed railway shortens the space and time distance,accelerates the flow of information,knowledge and other factors,and gradually forms a mature network structure.Therefore,taking the five major city agglomerations as examples,this dissertation firstly uses the accessibility index,spatial autocorrelation method and traffic equal-time loop measurement to conclude the spatial-temporal compression effect caused by the opening of high-speed railway.Secondly,the characteristics of high-speed railway network are summarized by means of social network analysis.After that,based on the analysis of the development and agglomeration level of producer services,this dissertation estimates the impact of the opening of high-speed railway on producer services and their subdivision industrial by Multi-period difference-in-difference Model.The difference of city size and time lag of high-speed rail effect are further discussed.Finally,with the help of multiple regression models,the dissertation analyzes the influence of the accessibility of high-speed railway,the centrality of high-speed railway network and other factors on producer services and their subsectors.This dissertation mainly draws the following conclusions:1.The high-speed railway effectively shortens the travel time between cities,and the compression effect of time distance is notable.Travel time varies due to geographical location and the complexity of internal administrative divisions.Highspeed railway promotes more balanced urban accessibility within mature urban agglomerations,but increases the difference in urban accessibility within rapidly developing urban agglomerations.2.The accessibility of urban agglomerations shows a significant positive spatial correlation,and features of low-low and high-high agglomeration are obvious.The first-tier cities at the railway line intersection are the central cities with good accessibility in the urban agglomeration.Affected by the geographical location,the number and the direction of railway lines,the isotime circle of the central city shows two forms: the axial distribution and the circular structure.3.The characteristics and centrality of high-speed railway network in the five major urban agglomerations are notable and there are obvious regional differences.Under the influence of regional proximity and high-speed railway lines,a number of subgroups with a certain degree of cohesion are formed among the cities,and the highspeed railway network presents a multi-center,multi-level,networking spatial pattern.4.The influence of high-speed railway on producer services is a dynamic process from positive to negative,and there is obvious heterogeneity in the subdivision industries of producer services.Producer services in cities of different sizes is affected differently by high-speed railway: The impact of high-speed railway on the productive service in large and medium-sized cities is agglomeration,while this effect in small cities is siphon effect.Some city agglomeration and individual subdivision industries has a lag period of 2-6 years.Accessibility and network centrality of high-speed railway have significant impacts with similar degree on producer services.Income level,government intervention,informatization level,investment level and knowledge level are also influencing factors for producer services.On this basis,this dissertation puts forward suggestions from two aspects: highspeed railway construction and producer services development.Finally,we summarizes some limitations of this dissertation and proposes the research prospects.